Typically, a discharge amount of tap water used in each, home varies depending on an installed position, of a faucet device, even when using the water pipes of the same size, and the water pressure and the discharge amount flowing through the water pipe vary due to an installed position of a water tank and a difference in interval between the water tank and each faucet device. Further, in the case of an aging water pipe, the discharge amount varies with foreign matter such as an internal scale or the like.
Since the aforementioned water pressure is proportional to the dimension of the water pipe and the amount of water that can be discharged within a limited time, in a faucet device with a weak water pressure of the water pipe, a small amount of water is discharged within in the same amount of time, and meanwhile, in the faucet device with a string water pressure, a relatively lot of the amount of water is discharged.
Accordingly, the high-rise buildings and the low-rise of the high-rise apartments have a problem that it should accept a loss generated by the waste of some of the discharge; amount due to the water pressure more than necessary.
In consideration of such a problem, a flow control device which measures the water pressure of the water pipe and reduces the cross-sectional area of the water pipe so as to match the reference value has been attached and used. Thus, since the flow rate is controlled by controlling the area, regardless of the internal water pressure of the water pipe, many types of required flow control devices need to be manufactured depending on the dimension and the water pressure of the water pipe, and since a specific flow control device is mounted after visiting each house to measure the dimension of the water pipe, the water pressure and the discharge amount and after disassembling the valve, there is a problem in that a lot of labor and time for mounting the flow control device are taken.